Various block copolymers of conjugated alkadienes have been disclosed and investigated in the prior art. Some of these polymers exhibit the desirable properties of the thermoplastic elastomers. These polymers are elastomers with sufficient tensile strength to make them useful in rubber applications without curing or crosslinking. These polymers can, therefore, be processed like thermoplastic materials and used like rubber polymers.
One physical property that is of considerable importance for thermoplastic elastomers is the elongation. Desirably the elongation of an elastomeric polymer should be high.